diff --git a/.github/workflows/build-and-deploy-docs.yml b/.github/workflows/build-and-deploy-docs.yml
index ecbef6f3..0238c703 100644
--- a/.github/workflows/build-and-deploy-docs.yml
+++ b/.github/workflows/build-and-deploy-docs.yml
@@ -25,7 +25,7 @@ jobs:
         id: extract_hash
 
       - name: Install nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v30
 
       - name: Nix cache
         id: cache-nix-packages
diff --git a/.github/workflows/build-project.yml b/.github/workflows/build-project.yml
index 45a5eef1..2610184c 100644
--- a/.github/workflows/build-project.yml
+++ b/.github/workflows/build-project.yml
@@ -22,6 +22,6 @@ jobs:
       - name: compile-env is self
         run: just _ci-compile-env-hack
       - run: just cargo build
-      - run: just cargo test
       - run: just cargo build --release
+      - run: just cargo test
       - run: just cargo test --release
diff --git a/design-docs/README.md b/design-docs/README.md
deleted file mode 100644
index 3056823b..00000000
--- a/design-docs/README.md
+++ /dev/null
@@ -1,52 +0,0 @@
-# Modified mdbook
-
-I made some modifications to the base mdbook setup to make it more suitable for scientific writing.
-The main changes are:
-
-1. Bibliography support using pandoc / citeproc.
-2. Equation / figure numbering and references.
-3. Greatly improved support for footnotes, end-notes, asides, and qualifications.
-4. Support for glossaries.
-5. Support for embedded YouTube videos.
-6. Improved support for plantuml (linked diagrams are supported).
-7. Revised page layout (I removed the left/right arrow bar and widened the page to make mobile reading easier).
-
-## Building the book
-
-It is possible to manually install all the needed dependencies and build the book, but it is much easier to use the provided [nix](https://nixos.org/) shell.
-
-Once you have installed `nix`, you can build the book by running:
-
-```bash
-nix-build --attr book
-```
-
-or, if you are using nix flakes:
-
-```bash
-nix build
-```
-
-## Developing the book
-
-I provided a nix shell that contains all the needed dependencies for developing the book. You can enter the shell by running:
-
-```bash
-nix-shell
-```
-
-or, if you are using nix flakes:
-
-```bash
-nix develop
-```
-
-Once you are in the shell, you can build the book by running:
-
-```bash
-cd src/mdbook
-mdbook build && mdbook serve
-```
-
-Then open a web browser and navigate to `http://localhost:3000` to see the book.
-The page should live update as you edit the markdown files.
diff --git a/justfile b/justfile
index f6c14928..96d17adb 100644
--- a/justfile
+++ b/justfile
@@ -19,8 +19,8 @@ SHELL := shell("""
   echo ${SHELL:-sh}
 """)
 
-set shell := [x"${SHELL:-sh}", x"-euo", "pipefail", "-c"]
-set script-interpreter := [x"${SHELL:-sh}", x"-euo", "pipefail"]
+set shell := [x"${SHELL:-bash}", x"-euo", "pipefail", "-c"]
+set script-interpreter := [x"${SHELL:-bash}", x"-euo", "pipefail"]
 set dotenv-load := true
 set dotenv-required := true
 set dotenv-filename := "just.env"